Steering lock device for a motor vehicle

ABSTRACT

A locking device for a motor vehicle having a steering column has a blocking bolt that locks the steering wheel shaft in the steering wheel column, wherein the blocking bolt is movable between a first and a second position, a return element that returns the blocking bolt to the first position, and at least one protection cover that at least partially covers the return element. In the first position, the blocking bolt is in blocking engagement with the steering wheel shaft. In the second position, the blocking bolt is disengaged from the steering wheel shaft. The return element is a torsion spring. The torsion spring is a coil spring with a coil body and a connection hook. A first end portion of the torsion spring has a hook extension, and is inserted into an opening of the blocking bolt and is covered at least partially by the blocking bolt.

BACKGROUND

1. Technical Field

The invention relates to a locking device for a motor vehicle.

2. Related Art

Locking devices for locking of a steering wheel column of a vehicle arewell known in the prior art. In the WO 2011/104017 A1 such a lockingdevice is disclosed.

In this locking device a blocking bolt is movable between a first and asecond position for locking the steering wheel shaft in the steeringwheel column. In the first position the blocking bolt can be broughtinto blocking engagement with the steering wheel shaft and, in thesecond position, is disengaged from the steering wheel shaft. Thelocking device furthermore has a drive, which is located in a housing,for moving the blocking bolt. The blocking bolt is part of the steeringwheel column and is integrated in particular in the steering wheelcolumn

SUMMARY

A conventional locking device may be susceptible to theft. Since theblocking bolt is engaged into the steering wheel shaft by a spring thedisengagement of the blocking bolt may be easy to achieve by destroyingthe spring.

According to one or more embodiments of the present invention, asteering lock device for a motor vehicle includes a better securityagainst theft.

According to one or more embodiments of the invention, a return element,which presses the blocking bolt into the blocked position, is at leastpartially covered by at least one protection cover.

By covering the return element this element is less accessible tothieves than conventional devices, or totally inaccessible for thieves.For this reason it is more difficult to destroy the return element withthe intention to disengage the blocking bolt from the steering shaft. Soa vehicle having such a locking device is better secured againstthieves.

In one or more embodiments of the invention, a drive with transmissionelement is provided to move the blocking bolt from the first to thesecond position, wherein the transmission element comprise a protectioncover to cover the return element at least partially. In one or moreembodiments of present invention, the effort for realizing a protectioncover is increased, because the protection cover can be realized with adouble function element, which belongs to the transmitting element andis simultaneously realizing a transmission and a protection function.

According to one or more embodiments of the present invention, atransmission element comprises a pivotable arm as transmission elementand as protection cover, which covers the return element at leastpartially. Since a pivotable arm as part of transmission element foroperating the blocking bolt is usually built very robust it can be usedin an appropriate arrangement as solid protection cover preventing thereturn element from violent destruction.

According to one or more embodiments of the present invention, thereturn element is a torsion spring. A torsion spring is an effective wayto realize a reliable return element with low costs. Furthermore atorsion spring allows to be covered at least partially by a transmissionarm.

According to one or more embodiments of the present invention, thetorsion spring is a coil spring with a coil body and a connection hook.This configuration constitutes a compact form in the area of the coilbody and allows a longitudinal extension to an appropriate place, wherethe return force of the torsion spring should be coupled to the blockingbolt and/or a corresponding fix point to fix an end portion of thetorsion spring.

According to one or more embodiments of the present invention, at leastone additional protection cover is provided to cover the coil body atleast partially. Since the coil body of a spring has a compact form incontrast to the longitudinal end portions like a connection hook it isadvantageous to cover different parts of the torsion spring withdifferent protection covers.

Accordingly, the cover for the coil spring can have a correspondingcompact form adapted to the coil body and a longitudinal end portionlike a connection hook can be covered by a longitudinal element like atransmission arm.

According to one or more embodiments of the invention, the additionalprotection cover is formed in a frame of the steering wheel column. Sothe coil body is protected in a very safe manner thereupon no additionalseparate part has to be manufactured.

According to one or more embodiments of the present invention, an endportion of the coil spring has a hook extension projecting from the coilbody to the blocking bolt and is covered at least partially by thepivotable arm. With this combination of features the coil spring isconnected to the blocking bolt assuring the safe engagement of theblocking bolt in the steering wheel column when no active disengagementis driven by the drive of the transmission element. At the same time thehook extension of the coil spring is covered by the pivotable arm andprotected against violent destructions.

According to one or more embodiments of the present invention, the hookextension as a first end portion of the torsion spring is inserted to anopening of blocking bolt and covered at least partially by the blockingbolt. This construction gives a safe mechanical coupling of the coilspring to the blocking bolt, wherein the first end of the hook extensionis secured against undesired access from outside.

According to one or more embodiments of the present invention, thepivotable arm covers at least partially a guiding and holding elementfor the blocking bolt. In this arrangement the pivotable arm can operatethe blocking bolt for disengagement from the steering wheel shaft orfrom the groove collar of the steering wheel shaft. At the same time thepivotable arm protects the blocking bolt against undesired removal outof the guiding and holding element.

If the guiding and holding element is a hollow profile formed in theframe of steering wheel column, there is no separate guiding and holdingelement necessary. Furthermore such a guiding and holding element formedin the frame is very difficult to destroy violently In one or moreembodiments of the invention, the blocking bolt is secured in the hollowprofile building the guiding and holding element and protected by acorresponding protection cover, in example by the pivotable arm.

According to one or more embodiments of the present invention, a secondend portion of the torsion spring extents from the coil body into anopening of a central holding pin formed in the frame of the steeringwheel column. In this way a second end portion of the torsion spring isfixed at the frame of the steering wheel column, wherein the point offixing is not accessible from outside and therefore protected againstviolation.

According to one or more embodiments of the present invention, theprotection cover for the return element is realized by the transmissionarm and at least one additional protection cover, which surrounds thereturn element at least partially.

According to one or more embodiments of the present invention, furtherincrease of safety may be accomplished, if the blocking bolt has arecess in which the pivotable arm is arranged. By this arrangement theblocking bolt is secured by the pivotable arm against a removal out ofthe guiding and holding element.

According to one or more embodiments of the present invention, theguiding and the holding element has a recess in which the pivotable armis arranged. In this arrangement not only the blocking bolt is securedin the guiding and holding element but further the transmission arm,which can be removed from the guiding and holding element in only in onedirection of movement. So it is facilitated to secure the transmissionarm at the frame.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is showing a side view to a locking device according to one ormore embodiments of the present invention in the first, locked positionof the blocking bolt,

FIG. 2 shows the device according to FIG. 1 in the unlocked secondposition of the blocking bolt,

FIG. 3 shows an extract of the arrangement of return element andblocking bolt in the frame of the device in the locked, first positionof the blocking bolt in a sectional representation,

FIG. 4 shows the extract of FIG. 3 in the unlocked, second position ofthe blocking bolt,

FIG. 5 is showing a perspective view to a part of the locking deviceillustrating the arrangement of the pivotable arm as protection cover,

FIGS. 6 and 7 are showing the arrangement of the pivotable arm, thereturn element and the blocking bolt in two difference viewingdirections,

FIG. 8 is showing a further perspective detail and

FIGS. 9 a and 9 b are showing one or more embodiments of the presentinvention in perspective view.

DETAILED DESCRIPTION

Embodiments of the invention will be described below with reference tothe drawings. In embodiments of the invention, numerous specific detailsare set forth in order to provide a more thorough understanding of theinvention. However, it will be apparent to one of ordinary skill in theart that the invention may be practiced without these specific details.In other instances, well-known features have not been described indetail to avoid obscuring the invention.

The locking device 1 of FIGS. 1 and 2 has a blocking bolt 2, which isable to engage to a steering wheel shaft or its groove collar in asteering wheel column in a first position 2′ (FIG. 1) and to disengagein a second position 2″ (FIG. 2).

A return element 4 in form of a coil spring is covered by a protectioncover 5, built by a transmission element 6, especially by the pivotablearm 7.

A first additional protection cover 10 covers a spring coil partially. Asecond additional protection cover 11 covers the return element 4 on theside faced to the steering wheel column 3 (see FIGS. 1 and 2). Theadditional protection covers 10 arid 11 are built or formed in a frame12 of the locking device 1.

A hook extension 13 extents from the coil body 8 ending in an endportion 14 in an opening 15 of the blocking bolt 2. The blocking bolt 2is guided and held in a guiding and holding element 16 between theblocked position 2′ (FIGS. 1) and 2″ (FIG. 2).

The coil body 8 is provided with a second end portion 17 extending intoan opening 18 of a holding pin 19 (see FIG. 5).

The blocking bolt 2 as well as the guiding and holding element 16 has arecess 20, 21, which is covered by the pivotable arm 7 (see FIG. 8).

FIG. 9 a is a schematic view of one or more embodiments of theinvention. The steering lock device is fixed to a steering column 25with a bolted clump 27. Steering lock device is partly covered with atrim cover 26 formed by plastic. The trim cover 26 is fixed to a housing28 with clicks (not shown) and removable from the housing 28 with theirelasticity shown in FIG. 9 b.

The steering lock device has a blocking bolt 2 that forms lockingcondition and unlocked condition. The bolt is inserted to a channel (notshown) of a steering shaft 24 when it forms locking condition.

In one or more embodiments of the present invention, the pivotable arm 7is fixed at a worm wheel 22 which is driven by worm 23 and a motor (notshown). Driven in clockwise direction by the worm wheel 22 the pivotablearm 7 is spaced apart the frame 12 of the steering wheel column. The endpositions of the pivotable arms 7 and the worm wheel 22 are shown inFIGS. 1 and 2.

The pivotable aim 7 is coupled with the blocking bolt 2 and moves thecoupled blocking bolt 2 from the locked position 2′ into the unlocked,disengaged position 2″.

The blocking bolt 2 is able to move into the locked position 2′ forcedby the return element 4, i.e., the coil spring 8. The steering shaft ofthe steering column is locked by the blocking bolt, which is pushed bythe spring into locking direction.

In unlocking direction the blocking bolt is pulled by theelectromechanical system described above. The spring-loaded bearing ofthe blocking bolt in locking direction is important, because a blockingbolt could be on top or ground of the tooth collar of the steeringcolumn. The steering column is locked by the blocking bolt, which ispushed by the spring into locking direction.

The locking of the steering column in the prior art could be destroyedby removing or destroying the spring. According to one or moreembodiments of the invention, the electronic steering column lock isprotected against any thief attack by covering the return element 4,i.e. the spring 8 at least partially by at least one protection cover 5.In one or more embodiments of the present invention, the transmissionelement provided to move the blocking bolt 2 comprise such a protectioncover to cover the return element. For this reason a complete cover ofthe electronic steering column 3 i. e. made of metal is disposablewithout any loss of security.

While the invention has been described with respect to a limited numberof embodiments, those skilled in the art, having benefit of thisdisclosure, will appreciate that other embodiments can be devised whichdo not depart from the scope of the invention as disclosed herein.Accordingly, the scope of the invention should be limited only by theattached claims.

REFERENCE SIGNS LIST

-   1 locking device-   2 blocking bolt-   2′ first position-   2″ second position-   3 steering column-   4 return element-   5 protection cover-   6 transmission means element-   7 pivotable arm-   8 coil body-   9 connection hook-   10 additional protection cover-   11 additional protection cover-   12 frame-   13 hook extension-   14 first end portion-   15 opening of blocking bolt-   16 guiding and holding element-   17 second end portion-   18 opening-   19 central holding pin-   20 recess-   21 recess-   22 worm wheel-   23 worm-   24 steering shaft-   25 steering column body-   26 trim cover-   27 bolted clump-   28 housing

1. A locking device for a motor vehicle having a steering column,comprising: a blocking bolt that locks the steering wheel shaft in thesteering wheel column, wherein the blocking bolt is movable between afirst and a second position; a return element that returns the blockingbolt to the first position; and at least one protection cover that atleast partially covers the return element, wherein, in the firstposition, the blocking bolt is in blocking engagement with the steeringwheel shaft, wherein, in the second position, the blocking bolt isdisengaged from the steering wheel shaft, wherein the return element isa torsion spring, wherein the torsion spring is a coil spring with acoil body and a connection hook, wherein a first end portion of thetorsion spring has a hook extension, and is inserted into an opening ofthe blocking bolt and is covered at least partially by the blockingbolt, and wherein a second end portion of the torsion spring extendsfrom the coil body into an opening of a central holding pin formed in aframe the steering wheel column.
 2. The locking device according toclaim 1, wherein a drive with transmission element is provided to movethe blocking bolt from the first to the second position, and wherein thetransmission comprises the protection cover.
 3. The locking deviceaccording to claim 1, wherein the transmission element comprises thepivotable arm and the protection cover.
 4. (canceled)
 5. (canceled) 6.The locking device according to claim 1, wherein at least one additionalprotection cover is provided to cover the coil body at least partially.7. The locking device according to claim 1, the additional protectioncover is formed in the frame of the steering wheel column.
 8. Thelocking device according to claim 1, wherein the connection hook of thecoil spring comprises the hook extension projecting from the coil bodyto the blocking bolt and covered at least partially by the pivotablearm.
 9. (canceled)
 10. The locking device according to claim 3, whereinthe pivotable arm covers at least partially a guiding and holdingelement that guides and holds the blocking bolt.
 11. The locking deviceaccording to claim 10, wherein the guiding and holding element is ahollow profile formed in the frame of the steering wheel column. 12.(canceled)
 13. The locking device according to claim 1, wherein thetransmission arm and at least one additional protection cover surroundand protect the return element.
 14. The locking device according toclaim 1, wherein the blocking bolt has a recess in which the pivotablearm is disposed.
 15. The locking device according to claim 1, furthercomprising: a guiding and holding element that guides and holds theblocking bolt, wherein the guiding and the holding element has a recessin which the pivotable arm is disposed.